Congenital bone marrow failure syndromes are characterized by abnormal hematopoietic cell growth, differentiation, and survival. Bone marrow transplant is the only available curative treatment, but is associated with significant side effects and limited by donor availability. The development of new therapeutic modalities calls for investigators with: 1. Expertise in bone marrow failure syndromes, 2. An understanding of the clinical implications of new molecular discoveries, 3. Experience in the design and implementation of clinical trials. Dr. Shimamura is a pediatric hematologist/oncologist with a molecular background in signal transduction and apoptosis. The proposed training program is designed to allow her to develop expertise in bone marrow failure syndromes and to gain experience in the design and implementation of patient-oriented research. Her long-term goal is to become an independent investigatory applying our understanding of molecular mechanisms of bone marrow failure to solve clinical problems. Dr. Shimamura will pursue her career development under the co- mentorship of Dr. Alan D'Andrea and Dr. David Nathan. Dr. D'Andrea's studies have uncovered a novel Fanconi anemia (FA) biochemical pathway. She proposes to study the clinical applications of these findings as follows: 1. Investigate the FANCD activation assay as a new functional screen for the FA pathway, 2. Screen for pharmacological agents that augment FANCD activation, and 3. Assess the effect of FA gene replacement therapy on the restoration of FANCD activity as part of the on-going Dana-Farber/Children's Hospital FA gene therapy project directed by Dr. Nathan. Dr. Shimamura has assembled a committee of expert advisors and collaborators to assist her in this project. Her project will be supported by several local core facilities and programs including the Fanconi Anemia Center, the Harvard Vector Laboratory, the Cell Manipulation and Gene Transfer Laboratories, the Clinical Gene Therapy Program, and the General Clinical Research Center at Children's Hospital. To complete her training, she will attend a bone marrow failure clinic at Children's Hospital, build a bone marrow failure repository for future independent studies, and complete course work on clinical research design, implementation and analysis.